I am trying to upgrade PHP from 5.2.6 to 5.3.2. I have created a directory C:\php5 and placed PHP in this directory including the php.ini file.

I have added C:\php5\ to the system's PATH variable and created a new variable called PHPRC to which it's value was set also to C:\php5\.

Whenever I run phpinfo(), I am presented with two pieces of information. They read as follows:

Configuration File (php.ini) Path -> C:\WINDOWS
Loaded Configuration File -> C:\php5\php.ini

Although I have the mysqli extension uncommented, I seem to unable to load this extension and use it. At least, I think that's what's going on because when I fire up phpMyAdmin (which used to work fine on 5.2.6) I get the following error:

Can someone please advise how I can go about changing the Configuration File (php.ini) Path from C:\WINDOWS to C:\php5?

Since PHP 5.3 mysql and mysqli support is built in, but functions mysql_get_client_info() and mysqli_get_client_info() are returning info string instead of simple version number like it did in PHP 5.2.x. This might confuse non-prepared applications, which would report "no mysql support" if the above functions are used to detect MySQL availability and expect simple number.

When you run phpinfo(), you can clearly see there, if MySQL and/or MySQLi supprort is available - there should be "mysql" and "mysqli" sections, if they are missing, there is no mysql/mysqli support.

If the problem with MySQLi detection is with phpMyAdmin only, I would suggest upgrading to latest phpMyAdmin, where the detection problem should be fixed.